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/*
* Connects to the local host at port 1234.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#define NSTRS 3 /* no. of strings */
/*
* Strings we send to the server.
*/
char *strs[NSTRS] = {
"This is the first string from the client.\n",
"This is the second string from the client.\n",
"This is the third string from the client.\n"
};
extern int errno;
main()
{
char c;
FILE *fp;
char hostname[64];
register int i, s;
struct hostent *hp;
struct sockaddr_in sin;
/*
* Before we can do anything, we need to know
* our hostname.
*/
gethostname(hostname, sizeof(hostname));
/*
* Next, we need to look up the network
* address of our host.
*/
if ((hp = gethostbyname(hostname)) == NULL) {
fprintf(stderr, "%s: unknown host.\n", hostname);
exit(1);
}
/*
* Get a socket to work with. This socket will
* be in the Internet domain, and will be a
* stream socket.
*/
if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
perror("client: socket");
exit(1);
}
/*
* Create the address we will be connecting to.
* We use port 1234 but put it into network
* byte order. Also, we use bcopy (see Chapter
* 14) to copy the network number.
*/
sin.sin_family = AF_INET;
sin.sin_port = htons(1234);
bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
/*
* Try to connect to the address. For this to
* succeed, the server must already have bound
* this address, and must have issued a listen()
* request.
*/
if (connect(s, &sin, sizeof(sin)) < 0) {
perror("client: connect");
exit(1);
}
/*
* We'll use stdio for reading
* the socket.
*/
fp = fdopen(s, "r");
/*
* First we read some strings from the server
* and print them out.
*/
for (i = 0; i < NSTRS; i++) {
while ((c = fgetc(fp)) != EOF) {
putchar(c);
if (c == '\n')
break;
}
}
/*
* Now we send some strings to the server.
*/
for (i = 0; i < NSTRS; i++)
send(s, strs[i], strlen(strs[i]), 0);
/*
* We can simply use close() to terminate the
* connection, since we're done with both sides.
*/
close(s);
exit(0);
}
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